Grade clamp



Aug. 23, 1932. JOHN 1,873,357

GRADE CLAMP Filed larch 2, 19:51

INVENTOR E 5 Z JOHN ATTORNEY Patented Aug. 23, 1932 'f UN D T' YS OFFICE 2 EvEREtrrsnJoHN, or wnsrronr, CONNECTICUT, AssIenoB To BELL TELEPHONE j 1 a iicationf ieanarcii 2,

This invention relates to supporting devices and morejparticularly to means for suspending electrical transmi sion cables from a messenger or supporting strand wh ch is firmly I i 5 attached to poles spacedat suitablejin'tervals along a transmission line- I The ob'ect of this invention is to provide a means which will grip the cable'sufiiciently to prevent it from slipping when the messenger not injure the cable sheath. V r r or sometime past it has been customaryto if) strand is on an angle ora down grade and yet I support aerial cables on a downgrade by' means of a grade clamp which consisted of a 13 piece these side pieces being provided with boltswhich secured themftogether around the strand and'the cable at the same time;

groove for the supporting strand was provid- -yedinthe upper part'of the side members while the lower portion of the clamp was formed to provide an opening for the cable,"

der' that the clamp would exert the proper amount of friction on the cable to be supported. Whenthe upper bolts of the clamp were tightened itcaused the clamp -to grip both the strand andthe cab le sheath. 'This'type of clampis highly objectionable due tothe fact that pressure may be very easily exerted, with the linemans wrench used for tightening these'bolts, to distort the cable seriously, since there is no way of telling when the clamp has been tightened sufficiently to grip the strand. Furthermore, at least two of the bolts must be removed inorder to place the clamp around the strand and the cable. Therefore, consid- 7 erablje time is consumed in fittingthecable in 'the clamp and also fitting the bushings in the clamp around the cable. 3 I 3 i 1 With these points in mind, the present supporting device has been designed bythe ap- 5n plicant in which the clamping of the cable .Qf iAiiEv pair" ofheavy steel or malleable iron side ORATORIES, moonrone rnn, or New-Yong, N. Y., A CORPORATION or. new YORK c AMi 1951 Ma No. 519,442.

rate and distinct'opierations since the device may be securely tightened to the strand without gripping the cable. The cable maybe then secured in the'lower portion of the device 1 without the use of abushing. Applicants device may be installediwithout removing any of the nuts and it cannot injure the cable sheath in any way. I I

An object of this invention is to prov idea supporting device for aerial cables. in which themeans for securing the supporting device to the strand ,is wholly independent of the 'mi-eansfor securing the, cableinthe device. p

A'further object of the present invention as the provision of asupporting devicefwhich may be easily and quickly'ins'talled with a minimum amount of labor.

still further object of thisinventionis to provide a'supporting device for aerial gcables'which will readily. conform itself'to the slight irregnlarities found in thecable sheath. the cables so spaced that the'cable'would be still furtherfobjectof'thisinvention is a supporting means for .aerial cables which provides a greater area of contactbwith increased friction between the clamp and the cablesheaththan has heretofore been possible. v Applicants improved device comprisesn pair 'of clamping members having longitudinal grooves therein, one 'pairrof which is adapted to engage the messenger strand and theother pair adapted to engage the upper edges of the members which surround the cables" to be supported. The members whichsnrround and grip the cable'comprise J V twoslieet steel side pieces having at their "upper edges longitudinal ribs, thelower edges of said members are bent back, and secured to the outsidelwall s of said side members by spot welding, to form a channel. Thesetwo side members are so ,formed'so as to conform pieces which encircle the cable. Each side of 'said side members is. divided into two clamping portions by means of a suitableislot cut therein. These "clamping portions are Fig. l illustrates in perspective the cable supporting device attached to a message]: Wire and supporting asection of aerial cable,

7 r I Iig..i2 is anexplodedend View: of .the de- ,yicewith .the cable removed. 1

Ref erringflnow to Fig. .1, .10 represents ,a

r messenger or supporting strand. fromrwhich goiithe lcable 11 isadaptedto bensu spendedlby .means of a supporting device which, grips the fcablefgll =independentlyof :the means Whiclifs'ecuresthefdeviceito the strand 'The" supporting device as shown in -Fig.1

. comprises, a pair of elongatedclamping members 12 and :13, these clamping members-have it 'longitujdinal groves]14-and.15 located along ithe'ir upper and lower edges, the upper, groove 1 l ibeing a daptedlto "receive the messenger or 30 supporting strand andthe lower. groove adapted to, receive theJupper edge 1670f the .rmembers 17 and1 8 Which surround the cable 7 to be supported. ZLocatedin the-members 12 .;and 13, are a plurality ot bolts v19, and 21.

fThesev bolts when tightened secure the strand 1() 3in, .the .uppengroove 14' :and-theQedges 16' ofthe members 17 and;1 8.in thelower groove 2 15. This tightening action, however, has. :no effect on .the'cablell and only serves tosecure '40 ,the. supporting; device to v the Q strand 10.

Theme nbers which surround and support the a cable 11 comprise .7 twowsheet steel, side '.'pieces 17 ,and. 18 formedito con-form to:the "shape of the cable 10. Each of saidside v pieces isrdivided into two portions22, and 23.

"This provides a,plurality of clamping surfaces -Whichare tightened separately'by meansfof the bolts 2 1v .an dA25 :Which are located in the channel vportionsiof the' side members 17 and 18.' v H r v Due 'to-the fa 'tjthat the portionsg22iand 23 of the side members, 17 and 18 are composed 10f; comparatively thin sheet: steel,,it'can-be readily observed I that :they. will contorm to r the slight,irregularities inthe: sheath of the 7 cable 10,1 and also insure a}. greateriareaiof contactithan' could be obtained if these members 'Were continuous, V

"As shown inFign-2, the'upper edgesldof i {the side members 17.=a nd, .18. are ribbed longi- V tudinallyto provide va; gripping. surfaceffor the clampingmembers '12..and13. .Located n the side members 17 iand 18, are a series (of .embOsslngs 30, 31, ,32.and 33,Mto,,f urther V (S 7 trengthen and preventfthefnbending oflthe members 22 and 23 When the nuts 28 and 29 are tightened down thereon.

It has been found inactual trial installa tions that a considerable amount of time and labor is saved by the use of this-device. Due

.tovthe factithatethe meansforzsecuring the -:icable supporting device to the strand is Wholly independent of the means for securing the cable in thedevice the sheath of the cable Wii lllnotibedamaged, consequentlyithe}liie of "the cable w'illrbe materially:increased;

- stallations that thissupporting device will holdthe largestsize of aerial cable on the steepest' g ra'de Without the slightest injury tqthe cable. sheath.

(App'licants improved. cable supporting ,de-

It" has been found in numerous trial in-,

vice, is f such :a vast. improvement, v o VerQtl1e ,rpresent devices of .s'this.natiire thatljit lihas .inbeenv adoptedas standard ffor use in ,tlieIgBell system." r r [While thereisshoivh and described herein the-preferred embodimentof,ihefinventionit 1 is .nnderstood that it .is not ,limitedror. lcon- .Ifinedgtoi'the precise details of construction herein disclosed, as variousmodifioations may .fbemade Without departing fromvlthe spirit of ztheinvention. a i v 1:, r

: What-isclaimed is:

v 1.,ln1acable supporting device.

besecured :to a, supporting. strand; a pain of I clamping. members, .longitudinaljgrooves in each .of. said Hmembers, .means in said clamp- I ingsmembers for securing them together, va pair of cable ,receivingimembers lsecuredin 10o certainof said groovesIandgmeansllocated gat v[therbottomnot,said cablefreceiving; members ,"forl securingr the. cable therein- 2.LlInr a, cable supporting device 2 I .1 be secnredtd supporting .strand,;a}pa ir,;of clamping members, longitudinal grooves in reach of, said-members, means passingv through saidrnembersjfor securingthem together, :a rp.air-. of zcabletreceiving members rigidly sei Qcured, attheir aippernedges in certain of; saidv 1 grooves and means pa ssing through ithe lower .edgesflof, said, members for compressing, said cable.receiving members,around said cable.

H 3. Ina cablesupportingdevice adapted to -::be secured to a (supporting strand, a paingof clamping memberspupper andflower grooves .in ,each ,of saidx members, smeansi -passing 'thr.o1 1gh:isaidvmembersfor-securing. themv together,,the upper grooves-1 arranged to grip l the l supporting strand while ,the {lower groovesare arranged-to grip the upper edges llofga pair of: cable,receivingv members, said :acable. receiving members: comprising, two meitallictsidepieces conforming =to ,the-. shape of ,theicable' to be supportedeand means located ,in thebottom: edges-of said members forsecuring the cable therein};

:In-Ha devicerfor suspending aeri'al cable asupporting strand, a pair 1 of clamp- 4 1g members upp n nd lower gr vesiin each of said members, means passing through said members forsecuring them together, the upper pair of grooves arranged to grip the supporting strand and the lower pair of grooves arranged to grip the upper edges of a pair of cable receiving members, said cable receiving members comprising a pair of me-' tallic members having ribs at their upper edges for engagement withthe clamping members, and said members curved to conform to the shape of the cable, slots in said.

side members for forming a plurality of gripping surfaces and to conform to slight irregularities in the cable sheath and means located in the lower edges of said members for securing said cable therein.

5. In a device for suspending aerial cable from a supporting strand, a pair of clamping members, upper and lower grooves in each of said members, means passing through said members for securing them together, the upper pair of grooves arranged to grip the supporting strand and the lower pair of grooves arranged to grip the upper edges of a pair of cable receiving members,said cable receiving members comprising a pair of me? tallic members, having ribs at their upper edges for engagement with the clamping members, said members curved to conform to the shape of the cable, slots-in said members for forming a plurality of gripping surfaces, the lower edges of the side members bent to form, channel portions therein and means passing through said channel portions for securing the cable therein. 7

6. A device for supporting aerial cable comprising a pair of clamping members having upper and lower longitudinal grooves therein, securing means passing through said members, the upper pair of grooves arranged to grip a supporting strand and-the lower pair of grooves arranged to grip the upper edges of a pair of cable receiving members, said strand and cable receiving members secured between said clamping members by said securing means and means located in the lower edges of said cable receiving members for securing the cable therein, said means being independent of the means for securing the clamping and cable receiving members to the supporting strands.

In witness whereof, I hereunto subscribe my name this 26th day of February, 1931. r

EVERETT ST. JOHN. 

